24 February 1995
Vol 267, Issue 5201

About The Cover

The firefly luciferase gene can serve as an effective reporter for gene expression in vivo. In this Arabidopsis seedling, the luciferase gene was fused to the promoter region of the CAB2 gene, whose expression is regulated by light and the circadian clock. Expression is greatest (red) in the cotyledons and absent (blue) in the root. See page 1161 and a related Report (page 1163) and News story (page 1091). [Luminescence image: S. Kay and A. Millar]